Drilling and cutting instruments have been developed specifically for arthroscopic procedures. These instruments can be advanced through a small incision to a specific site, forming a tunnel in bone. A cutting blade on the instrument can be deployed within the tunnel to cut a socket or other enlarged diameter section, which can be used PCL reconstruction, ACL reconstruction or other procedures.
One drawback of conventional cutting instruments is that some instruments feature large projections, gaps and other discontinuities on the exterior surface of the instrument, particularly in the vicinity of the cutting blade. Large discontinuities on the exterior surface, particularly in the area of the cutting blade, can be undesirable because bone fragments and other debris can become lodged in those areas and interfere with the operation of the instrument.
U.S. Pat. No. 8,888,781 discloses a combined flip cutter and drill instrument. The instrument includes a cone shaped drill head that projects from the end of a hollow shaft. The drill head can be operated in a “straight” configuration, in which the drill head is parallel to the axis of the shaft, to drill a tunnel into bone. The drill head can also be pivoted approximately 90 degrees to a “flip” configuration, in which the drill head is disposed at an angle with respect to the shaft, to perform a bone cutting operation. To allow the drill head to pivot, the shaft has a large opening at the distal end of the shaft and openings in the sidewall of the shaft. As noted above, large openings in the exterior of a cutting instrument can cause an issue when bone fragments and debris become clogged in the openings.
The flip cutter in U.S. Pat. No. 8,888,781 is capable of retrograde cutting to create sockets or tunnels in bone. However, there is no indication that the flip cutter can cut bone in an anterograde manner. As such, it is unclear whether the flip cutter can cut sockets for every application.